| **ACQUISITIONS, DIVESTITURES AND ASSET SALES - Acquisition of AJRD - Calculation of Consideration Transferred (Details) - USD ($) $ in Millions** |         | 9 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------------------------------|---------|----------------|
||
| **Business Acquisition [Line Items]**                                                                                                             |    |           |   |
| Fair value of consideration transferred                                                                                                           |    | $ 6,688        | $ 0 |
| Aerojet Rocketdyne Holdings, Inc.                                                                                                                 |    |           |   |
| **Business Acquisition [Line Items]**                                                                                                             |    |           |   |
| Cash consideration paid for AJRD outstanding common stock & equity awards                                                                     | $ 4,748 |           |   |
| AJRD debt settled by L3Harris                                                                                                                     | 257     |           |   |
| Cash consideration paid                                                                                                                           | 5,005   |           |   |
| Less cash acquired                                                                                                                                | (290)   |           |   |
| Fair value of consideration transferred                                                                                                           | $ 4,715 |           |   |

| X                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Payments To Acquire Business, Gross And Other
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash outflow associated with other payments to acquire businesses including deposit on pending acquisitions and preacquisition costs.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.
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| - Definition
The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.
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| X                                                                                                                                                              |
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